january translation tables

locals.entity.ts

import { Column, Entity, PrimaryColumn } from 'typeorm';

@Entity()
export class Locales {
	@PrimaryColumn({ nullable: false })
	code!: string;

	@Column({ unique: true, nullable: false })
	displayName!: string;

	@Column()
	enabled!: boolean;
}

query.ts

import type { ObjectLiteral, SelectQueryBuilder } from 'typeorm';

import type { ExecutePipeline } from '../orm/execute';
import { Translations } from './translations';

/**
 * Add i18n field to the query. The field is a json array of translations
 * for the given locales, if the locales is empty or contains '*' then
 * the i18n field is ignored.
 *
 * @example withI18n(qb, 'fr,en')
 * @example withI18n(qb, ['fr', 'en'])
 *
 * @param qb query builder
 * @param locales comma separated list of locales or array of locales
 * @returns join locale table and add i18n field to the query
 */
export function withI18n<T extends SelectQueryBuilder<any>>(
	qb: T,
	locales?: string | string[]
) {
	let localesArray: string[] = [];
	if (locales) {
		if (typeof locales === 'string') {
			localesArray = locales.split(',');
		} else if (Array.isArray(locales)) {
			localesArray = locales;
		}
	}

	const ignore = localesArray.includes('*') || localesArray.length === 0;
	if (ignore) {
		return qb;
	}

	localesArray = localesArray.map((locale) => locale.trim()); // remove whitespaces

	return qb
		.addSelect("'[' || GROUP_CONCAT(translations.i18n) || ']' as i18n")
		.leftJoin(
			Translations,
			'translations',
			`translations.entityId = ${qb.alias}.id AND translations.locale IN (:...locales)`,
			{ locales: localesArray }
		);
}

/**
 * Assign i18n field to the entity
 */
export function assignI18n<T extends ObjectLiteral>(): ExecutePipeline<T> {
	return (entity, raw) => {
		const out = Object.assign(entity, {
			i18n: raw.i18n,
		});
		return out;
	};
}

translations.entity.ts

import { Column, Entity, Index, PrimaryColumn } from 'typeorm';

@Entity()
@Index(['locale', 'entityId'], { unique: true })
export class Translations {
	@PrimaryColumn()
	locale!: string;

	@PrimaryColumn()
	entityId!: number;

	@Column({ nullable: false, type: 'simple-json' })
	i18n!: Record<string, string>;
}